Taper attachment for lathes



Dec. 31 1940. 5. E. CHEEVER TAPER ATTACHMENT FOR LATH'ES Filed July 11,1939 2 Sheets -Sheet 2 jaw 0% Patented Dec. 31, 1940 UNITED STATESPATENT OFFICE 2,227,178 TAPER ATTACHMENT FOR LATHES Application July 11,1939, Serial No. 283,852

11 Claims.

It has been customary when taper turning on a lathe has been desired, todisconnect the usual carriage feed and operatively connect the toolcarrier to a follower guided for feed motion by a templet bar at theback of the machine angularly adjustable to the longitudinal axis of thelathe bed to determine the angle of taper, the templet being heldagainst traversing movement with thetraversing carriage on which thetool carrier is mounted. The disconnection or connection of the hand orautomatic feed and the connection or disconnection of the tool carrierto the follower have previously been done as separate operations, theoperative connection or disconnection of the tool carrier to thefollower requiring that the operator go to the rear of the machine orreach across from the front if the distance is not too great. Theseoperations being independent for connecting or disconnecting the twotypes of feed, there is always the possibility that the operator maymake one connection without releasing the other, which might result inserious damage, if it were attempted to operate the machine under theseconditions.

One object of the present invention, therefore, is to provide a singleactuating means by which the connections to both controls are operatedtogether and in the proper relationship to each 30 other and by whichboth may be accomplished by the operator without requiring that he go tothe rear of the machine.

A further object is to provide mechanism by which combined straightand'taper turning may 3 be effected with the great accuracy which isrequired for repetitive work and in an expeditious and convenient.manner.

For a more complete understanding of this invention reference may be hadto the accompanying drawings. in which Figure. 1 is a fragmentary topplan of the tool. carriage portion of aelathe embodying the inventionand with the taper turning mechanism inoperative.

Figure 2 is a. re'ar'elevation of the same.

Figures 3, 4, 6 and 7 are detail sections on the correspondinglynumbered section lines of Figure 1, Figure 3 being shown also as takenon the section line 3-3ofFigure 6'.

Figure 5' is a detail section on line 5-5 of Figurei;

liigurev 8 is a view similar to a portion of Figure- 6, but: showing thepartsin' taper turning condition.

Figure 9:- isa view similar to-a portion of Figure 3; butrshowing a.modification;

Figure is a somewhat diagrammatic view partly in top plan and partlybroken away and in section showing the relationship between the tool andwork for opposite directions of traverse, showing the modification ofFigure 9.

Referring first to Figure 6, at l is shown a portion of the bed of alathe having ways 2 thereon on which is slidably mounted guides 3 of atraversing carriage 4, it being understood that this carriage traverseslengthwise of the ways 2 in the usual manner. Said traverse may beeiiected by rotation of a from a gear casing 6 carried by the carriageand meshing withteeth of a rack bar 1 secured to the bed of the machinein the well known manner. Slidable on ways Ill (see Figure 2) transverseto the traversing direction of the carriage is a tool carrier II. Thiscarrier I I may be fed relative to the carriage when desired, whollyindependent of the traverse of the carriage, or where it is desired toproduce taper turning, means are provided for effecting a feed motion ofthe carrier proportional to and controlled from the traverse of thecarriage.

According to this invention means is provided by which at any selectedof a plurality of definite traverse positions of the carriage, the taperfeed mechanism may be thrown into action, and. where the normal feed ofthe carrier independent of the motion of the carriage is not operatedduring that portion of the traverse in which the taper turningattachment .is out of operation, the turning is straight. Thuscombinations of straight and taper turning may be readily effected bythrowing in or out the taper turning device at selected points in thecarriage traverse.

As shown the feed motion of the tool carrier may be producedindependently of the traverse of the carriage by the rotation of a feedscrew I5 journaled in the carrier and axially fixed with relationthereto, by the rotation of the hand feed wheel It. It will be notedthat the hub I! of this wheel (see Figure 7) is mounted on a reducedextremity I8 of the feed shaft, this reduced extremity being journaledin the end plate H) of the carrier which butts against the shoulder 29on the feed screw formed by the reduction in diameter of its outer end.This feed screw I5- is threaded through an elongated nut member 21 andwhen this nut member is held against axial movement relative to thecarriage 4, an axial motion of the screw l5 by reason of its turningwill produce a motion in the same direction of feed or retraction to'thetool carrier ll. uch holding'of the nut 21 against axial motion pinion 5projecting relative to the carriage 4 may be produced by tighteningagainst its outer end a clamp collar 22. As shown best in Figure 4, thisclamp collar is split and one portion as 23 has journ-aled therein ascrew 24 which is threaded into a nut 25 adjustably secured in theopposite portion 2'5. The nut 25 is externally threaded for engagementwith the internal threads in a bore 21 in the portion 26, so that it maybe adjusted axially therein by its turning, and its outer end is shownas cut away to form a polygonal head 28 which may be engaged with asuitable wrench for that purpose. When adjusted to the desired position,it may be held against turning as by the set screw 28. On the oppositeside portion 23 of the split collar, the screw 24 has a head 30 whichbears against the outer face of the portion 23. By turning the screw 24it is thus evident that the collar 22 may be expanded or contracted torelease or grip the nut 2|. This collar 22 is held against axial motion,and for this purpose it is shown in Figures 2 and 4 as provided with anend flange 32 which may be secured as by the screws at 33 to a membersecured to the rear side face of the carriage 4. When the clampingcollar is released, the nut 2| is free to be moved axially by rotationof the screw 15, for a limited distance, determined by the spacing ofopposite ends of the nut 2| from a sleeve 85 (see Figure 7) in which thescrew I5 is journaled and from a tubular casing 36 which houses the rearend of the screw l5. These spaces are shown at 31 and 38, respectively.

The taper turning attachment is constructed to move the nut 2| axiallyin accordance with the traversing motion of the carriage 4 and for thispurpose it has a boss 48 depending therefrom on which is rockablymounted a cam follower 4| (see Figure 1). This cam follower is in theform of a rectangular block having a hole to rockably receive the boss48, this block riding between upwardly extending side wall members 43and 44 of a former cam 45. This former cam is shown as adjustablysecured to a bracket member 46, the adjustability permitting it to beadjusted to the desired angle to the direction of traverse to controlthe amount of taper. As shown it is securable at one end through a boltand slot connection at 58, and its opposite end may be provided withsegmental gear teeth 5| for engagement with an adjusting pinion 52 whichmay have a squared hub portion 53 by which it may be turned. This cammay be fulcrumed adjacent to its center to the carriage 4 as by thepivot bolt 55 shown best in Figure 3. The bracket 46 is slidably mountedwith reference to the carriage 4 in the direction of traverse of thecarriage, this carriage being provided with an extension 68 having thespaced depending webs 62 to the lower edges of which are secured theretaining bars 63 which support the side edge portions of the bracket46. A gib 64 may be employed to afford a sliding fit to the bracket 46with reference to the extension 68. This bracket 46 has a downwardextension 65 having an opening for the 'slidable reception of astationary bar 68 which extends along the back of the machine in spacedparallel relation to the ways 2 and is suitably secured. This bar 88 isprovided at spaced intervals with notches 18 at its under side and intoany of these notches may be projected when desired a locking finger 1|.This locking finger is keyed to a rock shaft 12 journaled in theextension 65 and between forks 14 projecting from the portion 63. Whenthe finger 1| is in its lifted position in engagement in any selected ofthe notches 10, the bracket 46 is held stationary during the traverse ofthe carriage, and as the carriage carries with it the nut 2| and thefollower block 4|, while the former cam 44 is held stationary with thebracket 46, any angularity of this former bar will cause a correspondingazn'al motion to the nut 2|. As this nut is held from rotation by theengagement of its boss in the block 4| and this block 4| between thewall members 43 and 44, this will result in axial motion of the feedshaft Hi and provided it is not rotated, a corresponding in or out feedmotion of the tool carrier H. To permit this axial motion of the nut 2|,the clamp 22 is released therefrom, and provision is made in accordancewith this invention whereby the clamping of the bracket 46 againsttraversing motion will release the clamping collar 22 and the clampingof the collar 22 will cause the release of the bracket 46 so that it maytraverse with the carriage. To this end the rock shaft 12 is slidablymounted through a forked extension 14 of the member 60 and has keyedthereto between the forks an arm 86 connected by a link 8| to one arm 82of a bell crank lever 83. This bell crank lever 83 is keyed to theclamp-actuating shaft 24 and is provided with an upstanding arm 85 towhich is pivoted the rear end of an actuating bar 86. This actuating barextends along one side of the tool carrier H and at its forward end ispivoted as at 81 to an actuating handle 88 fulcrumed at 89 on theforward face of the carriage g In the position of the parts shown inFigure 6, with the handle 88 in its forward position, the bell cranklever 83 is in such angular position as to clamp the collar 38 and holdthe nut 2| against axial motion relative to the carriage, and. thefinger 1| is out of engagement with the stationary bar 68 so that thebracket 46 is free to move with the carriage during its traverse. Underthese conditions and assuming the feed shaft l5 not rotating, there isno feed of the tool carrier during traverse, so that straight turning isaccomplished, although, if desired, a feed motion may be imparted byturning the feed wheel "5. By moving the handle 88 into the dotted lineposition of Figure 6, however, the rod 86 is pushed rearwardly, rockingthe bell crank lever 83 as shown in Figure 8, and releasing the clampingengagement of the collar 22 against the nut 2| while bringing the finger1| up into locking engagement with the stationary bar 68. The bracket 46is now held from motion with the traverse of the carriage 4, and thistraverse thus produces through the engagement of the follower 4| withthe now stationary former cam, a feed motion of the tool carriercoordinated with the traverse of the carriage thus to turn taper to anamount depending on the angular adjustment of the'former cam, therelease of the clamping collar v22 permitting such action to take placewith an axial motion of. the screw l5 unaccompanied by a rotary motion.During this traverse, the extension 60 of the carriage travels along therock shaft 12 which is held locked to the stationary bar 68.

It will thus be seen that it is quite unnecessary for the operator to goaround in back of or reach across the machine in order to render thetaper turning attachment operative or inoperative, and that it is alsounnecessary for him by a separate operation to render the screw feedmeans operative or inoperative; Both such actions are accomplished by asingle throw of the handle 88 and in a manner which insures only one ofthese feed mechanisms being operative at any one time. This would be ofparticular importance in any case where a power operation of the feedscrew is provided for, as is commonly done. As this is a commonpractice, however, it is not illustrated herein as per se it forms nopart of the present invention.

In Figures 2 and 3 the finger 1| fits closely in the notches 10. InFigure 9 the notches 'H' are shown as of greater width than thethickness of the finger H thus providing a limited lost motion which istaken up at the start of traverse so that the tool path is slightlydifferent in opposite directions of traverse. Where the direction ofactive traverse between the tool and the work is from the smaller to thelarger diameter portions, as shown by arrow A in Figure 10, the finger His held against one or the other side of the slot 1| depending on thetraverse direction, such that on the return direction of traverse thetool lags behind its cutting position so that its edge has a transverseposition corresponding to a larger diameter portion of the work than wascut on the working traverse. It is therefore relieved, out of contactwith the cut surface, during the return traverse and cannot score thecut surface.

From the foregoing description of an embodiment of this invention, itshould be evident to those skilled in the art that various changes andmodifications might be made without departing from the spirit or scopeof this invention as defined by the appended claims.

I claim:

1. In a machine of the class described provided with a support havingways, a carriage movable along said ways, a tool carrier movable on saidcarriage transverse to the directon of motion of said carriage, meanscontrolled by motion of said carriage for moving said tool carrierrelative to said carriage, means for operatively connecting anddisconnecting said controlled means, other means for producing motion ofsaid tool carrier relative to said carriage, a movable control member atthe front of the machine, and connections from said movable member tosaid connecting and disconnecting means and to said other means causingsaid connecting and disconnecting means to connect said controlled meansand render inoperative said other means in one position of said memberand in another position of said member to disconnect said controlledmeans and render operative said other means.

2. In a lathe having a traversing carriage, a tool carrier movabletransverse to the direction of motion of said carriage, a feed screw forsaid tool carrier, a bracket carried by said carriage for relativemovement thereto parallel to the direction of traverse, a former camangularly adjustable on said bracket, a follower for said cam, saidlathe including means for operatively connecting said follower to saidtool carrier, means for holding said bracket stationary while thetraverse of said carriage continues to cause said cam and follower tomove and control said tool carrier, means for rendering said feed screwoperative or inoperative by its turning to move said tool carrier, amovable actuating member, and means connecting said actuating member tosaid bracket-holding means and said rendering means causing said bracketto be held and said screw inoperative to move said carriage by itsturning in one position of said member, and said bracket to be releasedand said screw to be operative by its turning to move said carrier inanother-position of said member.

3. A lathe having a bed, a traversing carriage movable on said bed, atool carrier movable transverse tothe traversing direction, a feed screwmounted for rotation but axially fixed on said carrier, a nut threadedon said screw, a follower carried by said nut, a bracket carried on saidcarriage for movement relative thereto in the direction of traverse, astationary bar along which said bracket is movable, a former camangularly adjustable relative to the direction of motion of said carrierand in controlling relation to said follower, means for clamping orreleasing said bracket relative to said bar, means for clamping orreleasing said nut for motion relative to said carriage, a membermovably mounted on said carriage, and operative connections from saidmember to said two clamping and releasing means holding the one clampedand the other released in one position of said member and the onereleased and the other clamped in another position of said member.

4. A lathe having a bed, a traversing carriage movable on said bed, atool carrier movable transverse to the traversing direction, a feedscrew mounted for rotation but axially fixed on said carrier, a nutthreaded on said screw, a follower carried by said nut, a bracketcarried at the back of said bed on said carriage for movement relativethereto in the direction of traverse, a stationary bar along which saidbracket is movable, a former cam angularly adjustable relative to thedirection of motion of said carrier and in controlling relation to saidfollower, means for clamping or releasing said bracket relative to saidbar, means for clamping or releasing said nut for motion relative tosaid carriage, a member movably mounted at the front side of said bed onsaid carriage, and operative connections from said member to said twoclamping and releasing means holding the one clamped and the otherreleased in one position of said member and the one released and theother clamped in another position of said member.

5. A lathe having a bed, a traversing carriage movable on said bed, atool carrier movable transverse to the traversing direction, a feedscrewmounted for rotation but axially fixed on said carrier, a nut threadedon said screw, a follower carried by said nut, a bracket carried on saidcarriage for movement relative thereto in the direction of traverse, astationary bar along which said bracket is movable, a former camangularly adjustable relative to the direction of motion of said carrierand in controlling rela tion to said follower, said stationary bar.having notches spaced therealong, a locking finger movable into and outof any selected notch to hold said bracket stationary during continuedtraverse of said carriage, a clamp collar surrounding said of saidnotches, and holding said finger retracted when said clamp collar is inclamped condition, and means for actuating said connections from one tothe other of its conditions.

6-. A lathe having a bed, a traversing carriage movable on said bed, atool carrier movable transverse to the traversing direction, a feedscrew mounted for rotation but axially fixed on said carrier, a nutthreaded on said screw, a follower carried by said nut, a bracketcarried on said carriage for movement relative thereto in the d t iientra e e, a atio a a a on which said bracket is movable, a former camangularly adjustable relative to the direction of motion of said carrierand in controlling relation to said follower, said stationary bar havingnotches spaced therealong, a locking finger movable into and out of anyselected notch to hold said bracket stationary during continued traverseof said carriage, a clamp collar surrounding said nut and carried bysaid carriage, connections between said clamp collar and said fingerholding said collar unclamped when said finger is in one of saidnotches, and holding said finger retracted 1 when said clamp collar isin clamped condition,

and means for actuating said connections from one to the other of itsconditions, said connections including a toggle which is made when saidfinger is in one of said notches and is broken when said clamping collaris clamped.

7. In a lathe having a traversing carriage, a tool carrier on saidcarriage mounted for mo tion relative thereto transverse to thedirection of traverse, a bracket carried by said carriage at the back ofthe machine for movement relative to said carriage in the direction oftraverse, a former cam angularly adjustable with respect to saidtraversedirection carried by said bracket, a cam follower for said'camoperatively connected to said carrier, and means for selectively lockingor releasing said bracket in stationary position, a member movablymounted on the front part of said carriage, and operative connectionsfrom said member to said selective means.

8. A lathe having a traversing carriage, a tool carrier on said carriagemounted for movement transverse to the line of traverse, a feed screwjournaled for rotation in said carrier, a nut threaded on said screw,means holding said nut against rotation,

a clamp carried by said carrier 'in clamping relation to said nut, arock member,

and means operatively connecting said rock memher and clamp for closingor opening said clamp with relation to said nut on rocking of said rockmember.

9. A lathe having ,a bed, a traversing carriage movable on said bed, atool carrier on said carriage movable transverse to said traverse, abracket carried by said carriage for movement relative thereto in thetraverse direction, a stationary member along which said carriage ismovable, a former cam carried by said bracket and angularly adjustablerelative to the direction of traverse of said carriage, operativeconnections from saidformer cam to said tool carrier, and means actuableto locksaid bracket to said stationary member with a limited lost motionwhereby said tool traverses a slightly different path relative to thework during traverse of said carr age in opposite directions.

10. A lathe having a bed, a traversing carriage movable on said bed, atool carrier movable transverse to the traversing direction, a feedscrew mounted for rotation but axially fixed on said carrier, a nutthreaded on said screw, a follower carried by said nut, a bracketcarried on said carriage for movement relative thereto in the directionof traverse, a stationary bar along which said bracket is movable, aformer cam angularly adjustable relative to the direction of motion ofsaid carrier and in controlling relation to said follower, saidstationary bar having notches spaced therealong, a locking finger ofless thickness than the width of said notches movable into and out ofany selected notch to hold said bracket stationary during continuedtraverse of, said carriage and providing for lost motion between saidbracket and carriage which is taken up at the start of traverse in eachdirection, aclamp collar surrounding said nut and carried by saidcarriage, connections between said clamp collar and said finger holdingsaid collar unclamped when said finger is in one of said notches, andholding said finger retracted when said clamp collar is in clampedcondition, and means for actuating said connections from one to theother of its conditions.

11. In a machine of the class described provided with a support havingways, a carriage movable along said ways, a tool carrier movable on saidcarriage transverse to the direction oi motion of said carriage, meanscontrolled by motion of said carriage for moving'said tool carrierrelative to said carriage, means located at the back of the machine foroperatively connecting and disconnecting said controlled means, othermeans for producing motion of said tool carrier relative to saidcarriage, a movable control member at the front of the machine, andconnections from said movable member to said connecting anddisconnecting means and to said other means causing said connecting anddisconnecting means to connect said controlled means and renderinoperative said other means in one position of said member and inanother position of said member to disconnect said controlled means andrender operative said other means.

FRANK E. CHEEVER.

